Stereotype-plate-casting machine



o. WOHLRABE ET AL STEREOTYPE PLATE CASTINGMACHINE Filed May 12, 1924 Fg.4 Fig Saxony,

ing of the me necessary to 5 plate casting-machines has been w mantlemust be overcome erren STEREOTYPE-PLATE-GASTING meam i Application medma 12, 1924. Serial m. 712.785.

To all whom z't may camera Be it known that we, O''ro WOHLRABE andVIGTOR STEPHAN, both citizens of the German Republic, and residents ofPlauen, Germany, have invented certain new and useful Improvements inStereotype- Plate-Casting Machines, of which the following is aspecification.

Our inventon relates in general to stereo- W type-platecasting-machines, but more especially it relates 'to the casting-mouldfor or of such machines; one part of our invention concerns theintroduction of the metal into the mould; another part concerns theretainltherein, i. e. a -closing devce for the mould, and a third partconcerns certain means for actuating this device, as is all fullydescribed hereinafter.

Before entering into details we deem it give certain introductoryexplanations in order to facilitate comprehending the 'st of theinvention immediately it has een disclosed Hitherto the mould for or ofstereotypearranged either vertically or .horizontally. The object in thefirst case was to' utilize the advantage that the mantle of the mouldcan be easily moved o& the casting core, as no weight-work is requiredtherefor. But the advantage is more or less compensated for by thedisadvantage that it is necessary to run the casting metal into themould from the -upperfrontal side thereof whereby a lost 3 or dead headis produced and the necessity s entailed' to mend considerably theprinting jplate.

In the mending can be obviated by causing the 4%@ metal to' run into themould at a narrow longitudnal side thereof, but then the necessityarisesto lift the mantle towards the core, when the mould is to beclosed., that the prettyconsiderable weight of the bya correspondingexpenditure of power and work.

Another drawback common to known arrangements consists therein that .thecasting metal enters into the mould.

the case of horizontal casting moulds all these such a way that the aircontained in the mould must try to find its way outwards along thesurface of the flowing-in metal because this latter rushes into themould from ,above in the entire breadth thereof. It tlen 'occursoftentimes that more or less large air-bubbles cannotescape prior to themetal solidifying, whereby the casting is rendered porous.-

Now, in order to obtain and combine the advantages oflered by theknownarrangements, but to obviate at the same time the disadvantages ordrawbacks thereof, we have so devised the casting-mould (which may be avertical or a horizontal one) that the metal can be run thereintosimultaneously at its two small or narrow longitudnal sides, whereby thefollowing advantages are obtained:

First of all the mould in two separated currents, between which the aircan escape easily in upward direction without having any tunity to formpores in the metal. And as regards the product, printing plates can be,and are, produced which do not require any mending, such, for instance,as the .turning ofl of a lost or dead head. In the case of theemployment of vertical moulds the advantage may be utilized that 'tureof work worth mentionin is required to Convey the ladle to the mou d.

But what has been stated two paragraphs relates 'only to a part of ourinvention. Another' part relates to .means for `closing in .proper timethe communication between the ladle and the mould, the intention beingto keep liquid the metal at this particularly sensitive part of themachine while this latter is in o eraztion, or,

in other words, to prevent it m cooling no expendiopporin the precedingdown in the interval of time between two u caste, that is to say, duringthat time which the printing-plate cast solidifies. That occurs easilyif rotary slides: or l'ngitudinal slides are employed-as closing meansfor the mould, the 'liquid metal then remaina ing' in the simply-channelin the proximity* of the plate just ast The employment of those kinds ofslides, or mould closing means respectively, is the cause of manyinterruptions .of service, and besides, the life of the casting machineis Shortened and finishing the printing plates is retarded.

We have devised means to overcome the just mentioned drawbacks; theobject proper of these means (which are fully described hereinafter) isto force back the metal remaining in the supply-channel after thecasting-mould has been closed; in other words: that metal is removedfrom the proxmity of the mould until the printingplate cast hassolidified. That procedure s' the more desirable as then the first metalparticles arriving at the mould at the next casting operation getthereinto in hot and liquid state and are thus able to fill up theminute cavities of the matrix, as necessary.

We attain the object now in view by using specially devisedvalve-pistons instead of the usual ro-tary or' longitudinally movableslides, those pistons closing the mould in such a manner that thesuperfluous metal ing said channel.

is forced back into the ladle, as will appear more distinctly from thedetailed part of this specificatin following.

Our invention is illustrated by way of example in the accompanyingdrawing in which Figure 1 is a horizontalsection of the supply channelprovided to conduct the liq- 'uid metal into the mould; in other words:

it is a horizontal section of the parts form- Figure 2 is a front-viewof a valve-piston as mentioned above. Figure 3 is a vertical section ofthis piston in line C-C of `Fig. 4. Fig. 6

the plane A-A of Figure 1. Figure 4 is a vertical section of certainparts of a Stereo type plate casting machine which are shown in order tofacilitate Understanding the invention; the plane of section is B-B ofFigure 1, and the figure' is drawn on a reduced scale. Figure 5 is adiagrammatic illustration of the driving rods for two valve-pistons ofthe kind in question, according to is a section through the machineaccording to line D- D of Fig. 4.

The casting mould consists in known manner of a core 1 and a mantle 2,between which a space corresponding to the shape of the i printing platetobe cast is left. The core i and the mantle are provided with jacketsthrough which cooling water or another suitable cooling liquid is causedto flow.

The ,matrix is held fast at the mantle by a -lock 3. The casting mouldshown by way of example is a vertical one (Fig. 4) and the mantle istherefore, swingable on a vertical axis. The casting. metal shall beconducted into the above-mentionedspace at the two small or narrowlongitudinal sides or surfaces of the mould where suitably shaped slotsare provided for this purpose. These slots communicate with slots 4 and4' (*Figs.`

^erted on the piston by the the piston which forms a 1, 4 and 5). Themould is thus filled uniformly and 'quickly and the casting produced isof excellent quality, requiring no mending whatever.

The position of the slots or passages 4 and 4' with respect to the hasinor melting pot 5 containing'the liquid metal appears from Fig. 5, inwhich the side walls of the basin are indicated by dot-and-dash lines,as shown. Concerning the casting mould, the position of thesupply-channels is shown best in Fig. 4. The core of the mouldcommunicates with the basin or'melting pot 5 through an intermediatemember 6. There are two such members, one on either side of the twosmall or narrow longitudinal sides of themould, and in each thereof twocommunicating recesses are provided, of which one forms the passage 4and the other serves as space for the reception ofthe valve-piston 7Each of these pistons, of which there are two (Fig. 5), is formed by acylindrical body having a conical frontal head, as shown in the lefthandpart of Figure 1. One side of the piston is flattened, as at 8, Fig. 1;the rear end of the piston is flattened at four sides (Fig. 3) and aslot is milled thereinto for the reception of the end of a connectingrod 9 by which the piston is reciprocated as hereinafter described. Thepiston and the connecting rod are connected with each other by a bolt 11(Fig. 3) and by a 'pin 10 securing the bolt in its position in thepiston.

The milled slot provided in the piston for he iunction thereof with theonnecting rod is at its inner end shaped obliquely as indicated by thelines 12 and 12' in Fig. 5, the purpose being that one side of thepiston is able to take up fully the lateral pressure exconnecting rodwhen the mould is closed. a

Opposite the conical end 'of the piston 7. or 7' respectively, themember 6 is recessed correspondingly so that there is nearly noclearance when the piston has arrived at the end of its path, the liquidmetal being then forced away out of the valve space nearly completelyinto the basin or pot 5 through the channel 4.

The flattened side of the piston, or of each of the pistons 7 and 7respectivelyfls just over the matrix lock 3 behind which is a cavity 21into which extends a projection of part of the guiding me ns for thepiston.

The metal supplv channel 4 terminates in front of the conical end of thepiston so that 4 channel 4 during this movement .of the piston, andremaining therein until the next casting operation proceeds, remainsliquid and will again flow briskly into the space in front of the istonas soon as this latter is withdrawn, t ere being now no risk what everthat that metal will solidify prematurely, i. e. before the' Valvepistonis withdrawn. v V

In order to control the two Pistons re*- liably from a common point, weprefer to make use of the arrangement and combination of parts shown inFig. 5, in which either iston is connected by a rod 9, or 9'respectvely, with a bell-crank lever 16 16, or 15"/16" respectively, thetwo levers being connected with each other by a rod 17. The bell-cranklever 15716' has a third arm 18 to which is hinged a rod 19 by which thebell-crank levers are turned in the appropriate point of time from theposition shown in full lines into that indicated by dotted lines, andeversely. In other words: The

bell-crank levers 15716' is turned into the position 15"/16", and thebell-:crank lever is turned into the position l /l It ap'- pears fromFig. 5, that the members 9 and 15 on one side, and the members 9' and15' on the other side, co-operate like togglelevers so that theclosing-motion of the` pistns 7 and 7' is efl'e'cted with a considerablepower.

We claim:

1.` In a stereotype-plate casting machine, in combination: a castingmould having small longitudinal walls on opposite sides,

and members having metal supply channels terminating at said walls.

2." In ,a stereotype-pl-ate casting machine,

in combination, a vertical casting mould having narrow longitudinalwalls on op- A posite sides, and members having metal supply channelsterminating at'said walls.

3. In a stereotype-plate casting machine, in combination: a castingmould having small longitudinal walls on opposite sides,

and members having metal supply channelsterminating at said walls; amember located in front of each mould-supply channel and forming a spacecommunic ting 'therewith and extending practically at right anglesthereto; a' valve-pisten arranged to reciprocate in' saidspace andhaving a flattened side arranged to slide over the inlet aperture to themould-supply channel; and a main supply passage also provided in saidlatter member and terminating in :front ofsaid,pisten-valve,substantially' as set forth.

4. In a stereotype-plate casting machine,`

in combination, a vertical casting' mould having narrow longitudinalwalls on opposite sides, and members 'having metal supply channelsterminating a`t saidwalls;

'a member located in front of each mouldsupply channel and forming aspace communicating therewith and extending practic-ally at right anglesthereto; a valve-piston arrangedto reciprocate in said space and havinga flattened side arranged to slide over the inlet aperture to themouldsupply channel; and a main supply passage also provided in saidlatter member and terminating in front of said piston-valve,substantially as set forth.

5. In a sterotype-plate casting machine, in combination: a casting mouldhaving small longitudinal walls on opposite sides, 4

nected with each of the two valve-pistons which are arranged to move inopposite directions; a rod oonnecting the free arms of said levers witheach other, and means for actuating the said valve pistons by theintermediary of the said levers as set forth.

6. In a stereotype-plate casting machine,

in combination: a casting mould having small longitudinal walls onopposite sides,

and members having metal supply channels terminating at said walls;` amember located in front of each mould-supply channel and' forming aspace communicating therewith and extending practically at 'right anglesthereto; a valve-piston arranged to reciprocate in said spaceand havinga flattened side arranged to slide over the inlet aperture to themould-supply channel, and having at its opposite end a recess having anoblique inner end wall and' being ,adapted to recei've the end of aconnecting-rod attached to said valve-pisten in said recess, and meansto actuate this'rod; anda main supply pasrage also provided in saidlatter member and terminating in front of said pistonvalve,substantially as set forth.

7. `In a stereotype-plate casting machine, in combination, a verticalcasting mould having narrow' longitudinal walls on opposite sides, and'members having metal supply channels terminating at said walls;

a member located in front of each mouldsupply channel and forming aspace com-` municating therewith and extending practically at rightangles thereto'; a 'valve-pis- 'ton arranged to reciprocate in saidspace and having 'a flattened side arranged to' slide over the inletaperture to the mouldsupplychannel, and` having at its opposite :end arecess having 'an obliqu inner end wall and being adapted to receive'theend of a connecting-rod; a connecting-rod atsaid valve-pstons by theintermediary of tached to said valve-piston in sad recess the saidlevers, as set fOI'th. V thereof; a bell-crank lever connected with Intestmony whereof we aifix our signaeach of the two connecting rods; arod contures. a

5 meeting the free arms of' said levers with e OTTO WOI-ILRABE. eachother, and means for actuating the VICTOR STEP'HAN.

